Back for brake shoes



1.C.D.PETHS BACK FOR BRAKE SHOES Filed Sqpt; 2, 1922 Patented Get. 9, 1923.

units s'r res PATENT orifice."

CLIFTON 1). PETTIS, on NEW YORK, N. r.

BACK FOR BRAKE SHOES.

Application filed September 2, 1922. Serial No. 585,902.

Be it known that I, CLIFTON D. PnTTIs,

drawin formin a Dart of this sieeiiica tion.

My present invention has for its object to provide a simple, strong and effective construction of brake shoe back, my improved back being particularly well adapted for use in connection with that type of brake shoes in which the metal constituting the body of the shoe is united to the back in the casting operation. sists in the features of improvement hereinafter described, illustrated in the accompanying drawing and particularly pointed out in the claims at the end of the specification.

Figure 1 is a view in side elevation of my improved brake shoe back.

is an inverted plan View. Figure 3 is a view (parts being broken away) of the blank in which the back will be formed. Figure 4 is a sectional perspective View upon an enlarged scale, showing portions of the brake shoe back. 4

In the preferred embodiment of my invention, the back of the brake shoe is formed from a metal plate, as shown in Fig. 3, with notches 5 at its ends through which the cast metal may flow to form the end lugs of the shoe, in a manner well understood. At each side of the center of the shoe is formed an opening 6, which openings, when the shoe is completed, constitute the eyes in the sides of the raised lug B to receive the key whereby the shoe will be attached to the brake head in the usual manner. The body A of the back is cut away longitudinally to form the slots or openings 7 into which the cast metal will flow to aid in causing the back to firmly adhere to the body of f the shoe. The tongues 8 and 9 which are produced in making the opening 7 of the ack A are shown as each formed with side notches 10 and at the. ends of the tongue 8 are formed the projections 11, while at the ends of the tongue 9 are formed the projeotions 12.

When the back is cut as illustrated in,

The invention con- Figure 2 Fig. 3 of the drawing, the lugs 11 of the tongue 8 will be bent upwardly at right angles to the tongue, while the lugs 12 at the end of the tongue 9 will be bent clownwardly at right angles to said tongue and the blank will be folded upon the dotted lines at each side of the opening 6 to produce the raised center lug B, thus bringing the key openings 6 diametrically opposite each other beneath the crown of the lug B. 3 After the lug B has been thus formed, the

tongues 8 and 9 will be bent downwardly and inwardly, as shown 1n Figs. 1, 2 and 4 ot the drawing, so that these tongues over lap each other and so that the lugs 11 of the tongue 8 enter the notches 10 of the tongue 9, while the lugs 12 of the tongue 9 enter the notches 1O ofthe tongue 8. Preferably, the tongue 8 is bent upwardly at 14:, as shown in Fig. 1, so that the top surfaceof the tongue 8 is about thelevel of'the upper surface of the plate A, while the under surface of the tongue 9 is in line with the under surface of that portion of the tongue 8 at one side of the lug B.

While I have shown what I regard as the preferred manner of effecting the interlocking of the tongues 8 and 9, it is obvious that the overlapping tongues can be interlocked in other ways without departing from the scope of the invention. I am aware that it has been heretofore proposed to g strengthen the back plate of a brake shoe by forming the key opening 6 of the'lug B,

but with such construction, the tongues thus formed are not overlapped and interlocked,

as with my present invention. By forming the tongues 8 and 9 from the metal cut away in making the anchoring slots or openings 7 of the back A, the tongues can be made of such length that they will overlap and interlock and this is accomplished without the danger of weakening the shoe back adjacent the bottom of the center lug B. Vhen the tongues 8 and 9 are in overlapped and interlocked position, as shown in the draw ing, they serve to most effectively strengthen the back of the shoe at the part subjected to the greatest strain.

The precise details of construction above set out may be varied without departing from the scope of the invention and features of the invention may be employed. without it pt n as an entirety- Having thus described my invention what I claim as new and desire to secure by Letters Patent is 1. A back for brake shoes comprising a ductile metal plate adapted to extend lengthwise of the shoe and having a central attaching lug, and tongues cut from portions of the plate at each side of the base of the lug, said tongues being extended beneath the center lug and interlocked with each other.

2. A back for brake shoes comprising a ductile metal plate adapted to extend lengthwise of the shoe and having a central attaching lug and tongues formed integral With said plate and each arranged to eX tend beneath the central attaching lug sub stantially from side wall to side wall thereof to provide double reinforcement at this portion of the shoe.

3. A back for brake shoes comprising a ductile metal plate adapted to extend lengthwise of the shoe and having a central attaching lug and anchoring slots at each side of said lug, and tongues formed from the metal cut away in producing said anchoring slots, said tongues being bent downwardly and inwardly beneath the portions of the back plate adjacent the base of the attaching lug and having their ends overlapped and interlocked.

a. A back for brake shoes comprising a 1 ,avonm ductile metal plate adapted to extend lengthwise of the shoe and having a central attaching lug and tongues cut from portions of the plate at each side of the base 01": the lug, said tongues being extended beneath the attaching lug and one of said tongues being offset upward to receive the end of the opposite tongue.

5. A back for brake shoes comprising a ductile metal plate adapted to extend lengthwise of the shoe and having a central atta-ching lug, and tongues formed integral with the back plate and being bent inwardly beneath the attaching lug, each of said tongues being provided with an offset to enter a corresponding notch in the other tongue to cause said tongues to interlock.

6. A back for brake shoes comprising a ductile metal plate adapted to extend lengthwise oi the shoe and having formed integral therewith a central attaching lug, said back being provided with a long anchoring slot at each side of said attaching lug and tongues produced from the metal cut away to term said anchoring slots, said tongues being reversely bent beneath the attaching log and said tongues being formed With notches and provided with lugs to engage said notches when the tongues are overlapped.

CLIFTON D. PETTIS. 

